1. Field of the Inventive Concept
Some embodiments of the present inventive concept relate to methods of manufacturing three dimensional (3D) semiconductor memory devices. More particularly, embodiments of the present inventive concept relate to methods of manufacturing a 3D semiconductor memory device having memory cells arranged in a three dimensional manner.
2. Description of the Related Art
In order to meet increasingly stringent requirements of high performance and cost effectiveness in the field of semiconductor devices, it is desirable to increase the integration level of semiconductor devices. In particular, the integration level of a semiconductor device is an important factor in determining the cost of a product. Since the integration level of a conventional two dimensional (2D) memory device is generally determined by an area occupied by a unit memory cell, it is considerably affected by the micro patterning technology used to form the device. However, in order to achieve micro patterning, high-priced equipment is required. Accordingly, attempts to increase the integration level of the conventional 2D memory device are being made continuously. However, the results are still unsatisfactory.
To overcome the limitations of 2D device structures, 3D semiconductor memory devices including memory cells arranged in a 3D manner have been proposed. However, for mass production of 3D semiconductor memory devices, it is required to develop the technology for achieving reliable products while reducing the cost per bit.